Rootstock control of scion response to water stress in grapevine

Rootstocks play a major role in grapevine tolerance to water stress by controlling and adjusting thewater supply to shoot transpiration demand. This study aimed to characterize the influence of rootstockgenotypes in the adaptive response of scions to water limiting conditions. The effect of rootstock genotype(140Ru and SO4) was observed in the different availability of water provided to the scions (CabernetSauvignon, Grenache, Merlot, Syrah), while scions influenced stomatal control of water transpiration.Implication on the cell-to-cell component of plant water transport in both rootstock and scion impactedon embolisms formation in roots and on hydraulics of leaves. The main conclusion of the present studywas that rootstock and scion genotypes are able to confer to the plant traits of drought adaptabilityinfluencing respectively the capacity of water extraction from the soil and the sensitivity of the stomatal control.